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The invention relates generally to human-machine interfaces (HMI""s) and in particular to a dual mode interface for electronic devices providing improved access to the functions of those devices for people with disabilities.
The electronic touch screen is representative of current innovative HMI""s for electronic devices. With a touch screen, the user enters data by touching virtual buttons displayed on the computer display.
With a touch screen system, the type, size, and number of the virtual buttons may be readily changed by changing the computer""s program without changes in the associated hardware. Thus, the touch screen system offers a user-interface that may be flexibly tailored to a particular application. The ability to divide virtual buttons among different screens and to display only those screens needed by the user""s particular task can simplify data entry. The combination of text and graphical elements on the screen along with the virtual buttons can help to further guide the user through the steps of data input.
Normally, a touch screen system uses a touch screen panel which is placed directly over the viewing area of a standard computer display, for example, a CRT or a liquid crystal display (xe2x80x9cLCDxe2x80x9d). The touch screen panel provides a signal to a computer associated with the computer display indicating where on the surface of the display a stylus or finger is placed. This signal may be generated, for example, by acoustic systems detecting absorption of sound by a finger on the surface of the display or by systems using crossed beams of infrared light arrayed along x and y axes which are broken by the finger, or by laminated transparent electrodes which are physically compressed against each other to provide a point electrical contact that may be interpreted as an x and y coordinate.
Frequently a touch screen will be used with a computer contained within a device to be used by the public. The computer may have so-called multi-media capabilities providing both a visual and audio program intended to help members of the public obtain information or directions.
Despite the advantage of touch screen systems in such applications, like many novel interface controls, they present a barrier to many people with disabilities. Those with impaired vision perceive only the featureless surface of the display screen knowing that it may contain one or more virtual buttons of arbitrary placement and functions. Those unfamiliar with the language of the legends on the buttons or those who cannot read, are also foreclosed from much of the information presented by touch screen systems. Critical audio information in multi-media presentations will not be received by deaf users. Those with limited mobility may be unable to reach or operate the touch screen surface.
The predecessor applications to this application describe techniques for helping those with disabilities use a touch screen system. Similar barriers can be presented by other human machine interfaces where an ability to discern the pattern and purpose of the buttons (physical or virtual) requires high visual acuity and where operation of the buttons can require a high degree of mobility.
It would be desirable to find a method of making a wide variety of electronic devices more accessible to people with disabilities.
The present invention provides an HMI allowing a variety of electronic devices to be more accessible to a larger segment of the population. Generally, it does this by abstracting the control functions of the electronic device and special accessibility features into a standard set of buttons with recognizable orientation and standard operation and exposing this reduced button set control to the user in parallel with standard controls of the electronic device.
For this purpose, the conventional controls of the electronic device are mapped to a virtual list whose elements may be selected by two xe2x80x9cupxe2x80x9d and xe2x80x9cdownxe2x80x9d buttons and activated by a third xe2x80x9caccessxe2x80x9d button when it is released. The access button further operates when it is pressed in conjunction with an activation of a conventional control to provide an explanation of the function, operation or context of the conventional control. The selection and activation of elements on the virtual list can be accompanied by a spoken description and the explanation of the function can be via a spoken descriptions and or via display of the text in a larger font. In this way, a simple subset of controls can allow access to electronic devices having an arbitrary array of standard controls, either though use of the controls as augmented by the access-button invoked explanations or by dispensing with the standard control and navigating through the virtual list. The reduced button set including the access button, operating in addition to the standard controls, may be placed to be better reached and activated by those with decreased mobility.
Specifically then, the present invention provides an interface systems for an electronic device, the electronic device having a first set of electronic controls and a second set of electronic controls, the latter comprising an access switch, and up switch and a down switch. An electronic computer communicating with the first and second sets of electronic controls executes a stored program to respond to activation of ones of the first set of electronic controls to invoke functions of the electronic device. Activation of ones of the first set of electronic controls with activation of the access button provides information about the function invoked by the activated ones of the first set of electronic controls. The electronic computer further maps the functions of the electronic device invocable by the first set of electronic controls to list elements of a virtual list having a top and bottom. The program causes the computer to respond to the activation of the access switch to invoke a selected function of the virtual list and respond to the up switch and the down switch to change the selected function of the virtual list upward or downward.
Thus it is one object of the invention to provide a simple interface applicable to a wide variety of electronic devices that may increase their accessibility both to individuals with disabilities and to the general population.
It is another object of the invention to provide an interface that may be standardized and yet work for many different types of electronic devices.
The electronic computer may operate to respond to activation of the up or down switch to notify the user of a changed selected function. The notification may be, for example, in the form of spoken words.
It is another object of the invention to provide an interface to electronic devices that does not demand that the user have a high degree of visual acuity.
The access switch maybe a pushbutton and the electronic computer may be further operated to define activation of the access switch as release of the pushbutton.
Thus it is another object of the invention to allow a single access button to serve double duty both in invoking functions when it is released and for a secondary purpose, for example, in providing help or guidance on the other controls when it is depressed.
The virtual list may include a top delimiter list element at the top of the virtual list and/or a bottom delimiter list element at the bottom of the virtual list, respectively. The electronic computer may further operate such that the top and bottom delimiters are not invocable by the first set of controls (and thus do not correspond to normal device functions) but are invocable by the access button when selected to provide an indication of the location of the selection at the top or bottom of the virtual list.
Thus it is another object of the invention to provide xe2x80x9cphantomxe2x80x9d functions that allow improved navigation through functions of the electronic device when using the access buttons.
The electronic computer may operate so that pressing the up button when the selection is at the top delimiter or selecting the down button when the selection is at the bottom delimiter causes the selection to roll over to the bottom or top, respectively, only after an acknowledgment signal by the user. That acknowledgment signal may, for example, be a pressing of the access button.
Thus it is another object of the invention to prevent inadvertent rollover of the list such as may be confusing in operation of the device.
The present invention also provides an improved method of providing instructions on operation of the controls of the electronic device in the form of xe2x80x9clayeredxe2x80x9d help messages. This layered help system provides a second functionality to the electronic controls so that they operate normally when the access button is not pressed but when the access button is pressed to provide a description of the underlying function and its invocation is offered. Thus by pressing the access button and trying other electronic controls, a recitation of their function may be provided without activation the electronic device. In this way, the user may establish the layout of the various controls simply by trying them without adverse consequence.
Different users"" need for different levels of help is acknowledged through a layering process which responds to a first activation of a control with concurrent activation of the access button provides a first spoken xe2x80x9chelpxe2x80x9d message (e.g., the name of the control, its context, status and other information) while later activations of the control (prior to deactivation of the access button) provide a second different messages elaborating, in some respect, on the first spoken message. The help messages may also be displayed on a screen or the like. This process may be continued for subsequent activations of the button while the access button has not been released.
Thus it is another object of the invention to provide for an efficient audiovisual help system that accommodates both experienced users and those who wish additional assistance without unduly encumbering either.
The spoken messages may describe a name of the activated control and summary state of the operation of the activated control, or a function of the activated control and a detailed state of the operation of the activated control, or how the activated control is used, or special instructions related to the activated control, or a list of related controls or reference to a user manual page number. These notifications may optionally be provided sequentially in the order given.
Thus it is another object of the invention to provide increasing information about the function of the button organized according to the likelihood of its being valuable to the user.
The foregoing and other objects and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof and in which there is shown by way of illustration, a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference must be made therefore to the claims herein for interpreting the scope of the invention.